The present disclosure relates to a display device, a manufacturing method of a display device, and an electronic apparatus.
In recent years, forming light emitting layers (organic layers) of an organic EL (Electro Luminescence) display by a printing method has been proposed. A printing method has the advantages of a low process cost compared to that of a vacuum deposition method, and an ease in enlargement of the device.
This printing method is roughly divided into a non-contact system and a contact system. For example, an inkjet method and a nozzle printing method are known as methods of a non-contact system. These methods have the advantages of an ease in enlargement of the device and high material utilization efficiency. However, in these methods, it may be necessary to include a bank (partition) for providing an application position of ink, and there are cases where unevenness in the film thickness occurs within a pixel due to wet spreading of the ink or the like to the bank.
On the other hand, for example, a flexographic printing method, a gravure offset printing method, a reverse offset printing method and the like are known as methods of a contact system. While a flexographic printing method has advantages such as relatively high film thickness accuracy over the substrate, a short time necessary for printing, and a capability of an enlargement of the printer, the accuracy of a plate is low, and it is difficult to correspond to high definition and enlargement of the display device. While it is possible for a gravure offset printing method to have a high accuracy of a plate and to correspond to high definition and enlargement, the thickness distribution within a pixel becomes crest shaped, and there are cases where unevenness will occur in the light emitting luminescence.
Attracting attention within such methods has been a reverse offset printing method. A reverse offset printing method is a method which removes the ink of a non-printing portion by pressure contacting ink uniformly deposited on a transfer body to a plate, and transferring the pattern remaining on the transfer body to the body to be printed as a transfer pattern. In this reverse offset printing method, it is possible to have high definition patterning in addition to a more uniform thickness distribution.
Therefore, it is expected that a reverse offset printing method will be applied not only to the printing of light emitting layers of an organic EL display, but to the entire field of so-called printed electronics. Specifically, for example, applying the reverse offset printing method to the printing of wiring/insulation patterns of printed circuit boards, photoresists used by photolithography steps, color filters for displays, organic layers of organic TFT (Thin Film Transistors) and the like has been considered. An example of technology which uses such a reverse offset printing method is disclosed, for example, in [PTL 1].